ALLEN PARK -- Detroit Lions coach Jim Schwartz would only call it a leg injury after Sunday's win over the Chicago Bears, but Wednesday's official injury report confirms cornerback Chris Houston is dealing with a hamstring issue.

Houston was injured early in the fourth quarter during a punt. While blocking on the special teams play, he pulled up limping when running downfield. He was unable to return to action.

The Lions were without three of the team's four starting defensive backs for Wednesday's practice. Safeties Glover Quin (ankle) and Louis Delmas (knee) joined Houston on the sidelines.

Wide receivers Nate Burleson (forearm) and Calvin Johnson (knee) are the only other players who sat out on Wednesday. Defensive end Ezekiel Ansah (abdomen) and guard Rob Sims (shoulder) were limited participants.

The Green Bay Packers have already ruled out two players for Sunday's game against the Lions. Running back James Starks (knee) and cornerback Casey Hayward (hamstring) won't play according to coach Mike McCarthy.